In this trial, we will use a battery of mechanical and thermal Quantitative Sensory Tests (QST), using non-nociceptive and low-intensity painful stimuli, to identify a subgroup of patients with mechanical hyperalgesia. To overcome the well-known low response rate in trials with neuropathic pain patients, an enriched design comparing active drugs with placebo will be performed, including only patients with high intensity of on-going pain in combination with mechanical hyperalgesia as sequelae of different, but well defined neurological disorders. The blinded phase of the trial will be restricted to so-called responders, i.e. patients with a clinically meaningful pain reduction of at least 30% in the primary end point (mechanical hyperalgesia). The second objective of this trial is to evaluate, whether the anti-hyperalgesic effect of the active drug is dependent on the QST profile.